• Research in Plant Disease
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• v.11 no.2
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• pp.128-134
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• 2005

This study was conducted to elucidate effect of environmental factors on the development of white rot. In order to identify the causal agents causing white rot of Allium crops, we compared DNA profiles of a representative isolate, Sclerotium cepivorum, introduced from foreign country with Korean isolates using UP-PCR. As a result, Sclerotium isolates forming round-shaped sclerotia were identified as Sclerotium cepivorum pertaining in UP-PCR b group and Sclerotium isolates farming anamorphic-shaped sclerotia presumed to be a novel species of Sclerotium based on DNA profiles of UP-PCR. There was a big difference in DNA band pattern between two species of Sclerotium isolated in Korea. Electron micrographs of scanning electron microscope and transmission electron microscope showed morphological differences in sclerotial surface structure and rind layers between two species of Sclerotium. There were more wrinkles and pore spaces on sclerotial surface of Sclerotium sp. forming anamorphic-shaped sclerotia than that of Sclerotium cepivorum forming round-shaped sclerotia. Both of two white rot pathogens grew well at the temperature range of $10-25^{\circ}C$ with optimal temperature of $20^{\circ}C$. Sclerotia of the two pathogens were well formed at $20^{\circ}C$ and well germinated at the temperature range of $20-24^{\circ}C$, Effect of pre-incubation of sclerotia on destruction of sclerotial dormancy of two pathogens was evaluated through storing sclerotia under different temperature condition. The sclerotia of the two pathogens showed an increased capacity to germinate on potato dextroise agar when the sclerotia were incubated for 7 days at $10^{\circ}C$ after pre-treatment at $35^{\circ}C$ for 7 days. At that time, germination rate of Sclerotium sp. and 5. cepivorum was $100\%\;and\;70\%$, respectively. Flooding period and treatment temperature had an effect on sclerotial survival rate of the two pathogens. As flooding period and treatment temperature increased, sclerotial germination rate of the two pathogens decreased. It was confirmed that soil humidity played an important role on development of white rot. It was the highest disease incidence of garlic white rot when garlic were sown at potted soils infested with the two pathogens and adjusted soil humidity to $15\%$ (field moisture capacity, about -300 mb). As soil humidity increase or decrease based on $15\%$ of soil humidity, disease incidence decreased move and more.

• Research in Plant Disease
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• v.16 no.2
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• pp.163-169
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• 2010

To screen for potential biocontrol agents against postharvest disease of garlics caused by Penicillium hirsutum, a total of 1292 isolates were isolated from the rhizoshere or rhizoplane of Allium species. Among them, S59-4 isolate was selected as a potential biocontrol agent by in vivo wounded garlic bulb assay. The isolate was identified as Pantoea agglomerans (Pa59-4) through Biolog system. Pa59-4 did not inhibit the mycelial growth of P. hirsutum in dual-culture with P. hirsutum on tryptic soy agar. In order to elucidate mode of action of Pa59-4 on biological control, nutrient competition between Pa59-4 and P. hirsutum was investigated by the simple method using tissue culture plates with cylinder inserts containing defusing membrane reported by Janisiewicz et al. (2000). The results showed that Pa59-4 effectively suppressed spore germination and mycelial growth of blue mold in the low concentration (0.5%) of garlic juice, but it did not suppress those of blue mold in the high concentration (5%) of garlic juice. This result suggests that the mechanism in biocontrol of garlic blue mold by Pa 59-4 may be involved in nutrient competition with P. hirsutum on garlic bulbs.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.805-809
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• 2006

Background: In our previous study, we demonstrated that transforming growth factor-beta 1 receptor II(TGF-${\beta}1RII$) may have a role in the formation of bullae. In this study, we investigated if expression of transforming growth factor-beta 1 (TGF-${\beta}1$) ligand was altered in a bullous lung tissue by immunohistochemical staining of bullous tissues from patients with primary spontaneous pneumothorax. Material and Method: Bullous lung tissues were obtained from 36 patients with primary spontaneous pneumothorax, including 34 males and 2 females aged 14 to 38 years old. Result: Of the 36 patients, 19 were TGF-${\beta}1$ positive and 24 were transforming growth factor-beta 1 receptor II(TGF-${\beta}1RII$) positive. Among the 19 TGF-${\beta}1$ positives, 15 were also TGF-${\beta}1RII$ positive, observation at high magnification showed that strong immunohistochemical stain was detected in the boundary region between the bullous and normal lung tissues. Conclusion: These results suggest that overexpression of TGF-${\beta}1$ may be involved in the formation of a bulla as well as the alteration of TGF-${\beta}1RII$ expression. Further molecular studies are needed to elucidate the more detailed molecular mechanisms of the bulla formation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.1
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• pp.9-16
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• 2016

To investigate the effect of soluble silicate zeolite dressing of the rice against bakanae disease, field trial in reclaimed land and in vitro were carried out. The coated rice seeds (SCS) which were dressed with the mixture of 25% silicic acids (binder), and the zeolite (coating powder). In wet direct seeding, uniform scattering of rice seeds on the soil surface and the better seedling establishment were shown in SCS treatment plots. The incidence of bakanae disease began from the mid tillering stage toward the heading stage. Around heading stage, the ratio of infected tillers reached its highest point by 9.9% in non-SCS treatment plots. While, in SCS treatment plots, the ratio of infected tillers was no more than 0.01%. The vitality of the pathogenic fungi of bakanae disease in the SCS and non-SCS samples were assessed. Samples were incubated for one week keeping proper humidity at $30^{\circ}C$ after inoculated with panicles of infected rice plants from experimental field plots. In non-SCS treatment, pinkish colonies were formed on the grain surface of panicle of infected plants, and mycelium, macro-conidia and micro-conidia were developed actively inside part of infected grain inoculated. While in SCS treatment, micro-conidia and mycelium were not survived and the growth of macro-conidia, mycelia were greatly inhibited and withered. Based on the results, it is concluded that the environmental friendly control of bakanae disease by use of SCS is possible and soluble silicate can be applied as agents for replacement of seed disinfection.

• Journal of Sensor Science and Technology
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• v.11 no.1
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• pp.9-17
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• 2002

The forming conditions of X-ray storage phosrhors $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ have been investigated, and measured the PSL emission spectra and its intensity, fading characteristics and does dependence of the prepared phosphors. These characteristics were compared with those of commercial image plate (ST-III) obtained from Fuji Photo Film Co. The optimal preparing conditions of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ Phosphor were 0.5 mol% of $EuF_3$, 4.0 mol% of NaF and composition ratio x=0.3, and the sintering temperature were $950^{\circ}C$ in $H_2$ atmosphere. When the composition ratio x was equal to 0, the spectral range of the luminescence of $BaFBr_{1-x}I_x:Eu^{2+}$, $Na^+$ phosphor was $365{\sim}420\;nm$, and its maximum luminescence intensity appeared at 390 nm. When composition ratio x was not equal to 0, the wavelength ranges and peak of the spectra were shifted to the longer wavelength with the growth of composition ratio x. A good linearity was shown between the PSL intensity and X-ray irradiation dose. The phosphor sample with x=0.3 exhibited better fading characteristics than that of other $BaFBr_{1-x}I_x:Eu^{2+}$ phosphor samples, and the fading characteristics of the PSL intensity at room temperature were shown poorer with increasing $I^-$ ion concentration. The lattice constant of the phosphor becomes larger with increasing the $I^-$ ion concentration.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.337-344
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• 2009

This study was conducted to investigate the effects of various cropping system applied with cattle slurry on productivity of sorghum $\times$ sudangrass hybrid (SSH) and environmental pollution in paddy land. cropping systems used in this study were consisted of two designs, such as double-cropping sorghum $\times$ sudangrass hybrid followed by whole crop barley applied with cattle slurry (DSSCS) and mono-cropping sorghum $\times$ sudangrass hybrid followed by hairy vetch used as green manure (MSSGM). The field experiments were conducted on the clay loam at Backsanmyun, Kimje, Chunlabukdo province in Korea for three years (May 2006 to Apr. 2009). This study was arranged in completely randomized design with three replicates. The yield of dry matter (DM) of SSH in DSSCS increased significantly as compared with that of MSSGM (P<0.05). The contents of crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF) and total digestible nutrients (TDN) of SSH were not influenced by cattle slurry and green manure. The pH, and contents of OM, T-N and $P_2O_5$ in soil samples collected from DSSCS after the end of experiment were higher than those of MSSGM. The pH, and contents of OM in DSSCS treatment were remarkably higher than those at the beginning of the experiment (p<0.05). However, The pH, and contents of OM in MSSGM treatment were hardly influenced, as compared with those at the beginning of the experiment. The contents of T-N in soil samples collected both from DSSCS snd MSSGM treatments were remarkably higher than those at the beginning of the experiment (p<0.05). In addition, the concentrations of CEC in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (p<0.05). The concentrations of $NO_3$-N, $NH_3$-N and $PO_4$-P in leaching water were hardly influenced by the cropping system and application of cattle slurry.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.200-206
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• 2018

This study was to investigate the optimal condition of mixture ratio for development of functional food ingredient from Sarcodon aspratus and rice bran. First, $^{\circ}Brix$ was measured along with extraction time. Five kinds of mixtures of Sarcodon aspratus and rice bran (10:0, 7:3, 5:5, 3:7, 0:10) were extracted in $95^{\circ}C$ water over a one-hour period and the extraction yield was evaluated. We further evaluated ${\beta}-glucan$ content, DPPH radical scavenging activity, ferric ion reducing antioxidant power (FRAP), total phenolic content and total flavonoids content. As a result, both Sarcodon aspratus and rice bran showed a constant $^{\circ}Brix$ after 45 minutes of extraction time. The content of ${\beta}-glucan$ was highest in the Sarcodon aspratus and rice bran mixture with a ratio of 3:7. As the ratio of rice bran increased in all mixtures, the antioxidant capacity also increased. In conclusion, to create a functional food ingredient the optimal mixing ratio of Sarcodon aspratus to rice bran is 3:7.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.465-474
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• 1999

RNase activity of Saccharomyces cerevisiae ATCC 7754 was investigated to obtain strains with high ribonucleic acid (RNA) content. The yeast strain contained two RNase activities; an acidic RNase with a optima of pH $3{\sim}4$ and an alkaline RNase with a optima pH 9. The acidic RNase activity was inhibited by $0.08\;M\;HgCl_{2}$ most drastically. The alkaline RNase activity was inhibited by 2.0 M NaCl or KCl, while enhanced by addition of $0.05\;M\;CaCl_{2},\;0.02\;M\;ZnSO_{4},\;or\;0.008\;M\;HgCl_{2}$. Various mutants of Saccharomyces cerevisiae ATCC 7754 were isolated by ethylmethane sulfonate (EMS) treatment or $\gamma$-ray/ultra violet irradiation. Among the mutants that were sensitive to high concentration of KCl which inhibits alkaline RNase, B24 was selected for high RNA content per culture volume. Growth characteristics of the mutant were comparable to those of the mother strain with optimum growth at pH $4.5{\sim}5.5$. The mutant accumulated higher content of RNA than the mother strain when glucose was used as the carbon source. However, both growth rate and total RNA content of the mutant were higher in molasses medium than in glucose medium. RNA content of the mutant increased rapidly during the early stage of growth, and then decreased gradually until the culture reached stationary phase by a fed-batch culture in a 5 L jar fermenter. Maximal cell harvest and the final RNA content using the mutant B24 were 69.6 g/L culture broth and 19.8 g/100 g of the dry cell while those using the mother strain were 68 g/L culture broth and 16.1 g/100 g of dry cell, respectively.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.240-247
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• 2010

Pseudomonas aeruginosa is a Gram (-) opportunistic human pathogen causing a wide variety of infections on lung, urinary tract, eyes, and burn wound sites and quorum sensing (QS), a cell density-sensing mechanism plays an essential role in Pseudomonas pathogenesis. In order to investigate the importance of QS in the Pseudomonas infections of Korean patients, we isolated 189 clinical strains of P. aeruginosa from the patients in Pusan Paik Hospital, Busan, South Korea. The QS signal production of these clinical isolates was measured by signal diffusion assay on solid media using reporter strains. While most clinical strains (79.4%) produced the QS signals as similar level as a wild type strain, PAO1 did, where LasR, the initial QS signal sensor-regulator was fully activated, a minority of them (4.2%) produced much less QS signals at the level to which LasR failed to respond. Similarly, while 72.5% of the clinical isolates produced QS signals enough to activate QscR, an another QS signal sensor-regulator, some few of them (9%) produced the QS signals at much lower level where QscR was not activated. For further analysis, we selected 74 clinical strains that were obtained from the patients under suspicion of Pseudomonas infection and investigated the total protease activity that is considered important for virulence. Interestingly, significant portion of them showed very low protease activity (44.6%) or no detectable protease activity (12.2%). When the biofilm-forming ability that is considered very important in chronic infection was examined, most isolates showed lower biofilm-forming activity than PAO1. Similarly, significant portion of clinical isolates showed reduced motility (reduced swarming activity in 51.4% and reduced twitching activity in 41.9%), or non-detectable motility (swarming-negative in 28.4% and twitching-negative in 28.4%). Our result showed that the clinical isolates that produced QS signals at the similar level to wild type could have significantly reduced activities in the protease production, biofilm formation, and motility, and some clinical isolates had unique patterns of motility, biofilm formation, and protease production that are not correlated to their QS activity.

• Journal of Veterinary Clinics
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• v.29 no.2
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• pp.134-140
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• 2012

This retrospective study was performed to describe and evaluate ultrasonographic characteristics of splenic disorders and to pursue any relationship with cytologic or histopathologic diagnoses. Medical records were reviewed for patients that had undergone both abdominal ultrasonographic procedures and ultrasound-guided fine-needle aspiration (FNA) or surgical biopsy of splenic lesions or necropsy from January 2002 to July 2011 at Seoul National University Hospital for Animals. Total 124 dogs, 76 cases with FNA and 48 cases with biopsy, were available for this investigation. The age of dogs ranged from 2 to 17 years ($mean{\pm}SD$ = $9.54{\pm}3.34$ years), with the gender distribution of 61 females (26 spayed) and 63 males (40 neutered). In breed distribution, 114 were purebred dogs and 10 were mixed breed dogs. The dogs represented 26 breeds, with 113 dogs categorized into small-sized breeds. The ultrasonographic appearances of splenic disorders could be classified into 10 types including normal appearance, depending on the distribution and echogenicity of splenic lesions as well as the increase in spleen size and diffuse parenchymal changes. Among 124 cases, 44 (35.4%) had hypoechoic nodules/masses with the highest frequency, followed by 23 (18.5%) with multiple small hypoechoic nodules. Of 124 cases, 70 (56.5%) were benign and 54 (43.5%) were malignant lesions at cytologic or histopathologic results. Each ultrasonographic appearance had variable cytologic or histopathologic diagnoses. However, diffuse heterogenicity and diffuse hypoechogenicity were significantly associated with malignancy (p < 0.05), whereas hyperechoic nodules/masses were more often associated with benignity (p < 0.05). Based on our results, it may be considered that the ultrasonographic examination for spleen could be able to provide the least information necessary for benign and malignant lesions in prioritizing differential diagnoses.